A new study published this month in Animals provides further evidence that Trap-Neuter-Return (TNR) sustainably reduces populations of community cats, also called feral cats.

The study, by Daniel D. Spehar and Peter J. Wolf, tracked the impact of TNR on a colony of cats living along a trail adjacent to the San Francisco Bay, and they found that TNR was highly effective.

This study, and others like it, are a welcome reaffirmation of what we’ve known for decades. Starting in 1990, Alley Cat Allies has tirelessly promoted and championed TNR as the only humane and effective approach to community cats.

In TNR, community cats are humanely trapped (with box traps), brought to a veterinarian to be spayed or neutered, vaccinated, and eartipped (the universal sign that a community cat has been neutered and vaccinated), and then returned to their outdoor home to live out their lives. By breaking the breeding cycle of cats, it provides a non-lethal means of reducing cat populations.

In our work, Alley Cat Allies has seen time and again that TNR makes converts out of even the most reluctant.

But though TNR is now mainstream and widely considered common sense, there remain communities that have yet to adopt non-lethal cat population management. Many of them, particularly those headed by officials who are nervous to uproot the status quo, question TNR’s effectiveness. Sometimes they’re even led off course by propaganda about the relationship between cats and wildlife that too often makes sensational headlines.

With new research, then, comes another opportunity to show skeptics why so many towns and cities have embraced TNR.

In Spehar and Wolf’s study, they carefully followed a TNR project for a colony of 175 community cats over a 16-year period, between 2004 and 2020.  They found that the cat population declined by 99.4 percent, with no cats euthanized except for untreatable illness and injury.

Now, only one happy, well-loved cat remains.

Results didn’t take a decade and a half to materialize. In fact, only two years in, a major milestone was met: “no kittens were known to have been born in the program area after 2006.”

In the end, “the absence of new kitten births…along with the removal of adoptable adult cats and kittens and limiting the abandonment of pet cats, appeared to be the main contributors to the sustained decline in the community cat population over time.” That, the study clarifies, is the same conclusion reached by various other long-term TNR studies.

In the absence of TNR, shelter staff struggle with a constant influx of unadoptable community cats. After the Johnson County Animal Shelter in Indiana became a member of Alley Cat Allies’ Future Five: Shelter Partners to Save Cats’ Lives program and began TNR, the transformation was beyond words. Positive outcomes for cats increased by over 77 percent over the course of five years. In summary: there was no more killing of healthy community cats while calling it “euthanasia.”

Compared to catch and kill methods, that’s a stark difference not only in results, but in morality. You’d be hard-pressed to find heartwarming anecdotes from shelters with high kill rates for a variety of obvious reasons, but chiefly because decades of lethal policies have failed. If killing cats were effective, surely we’d have seen fruits of the cruel labor by now.

So, if you’ve ever gotten cold feet about speaking up in favor of TNR at a town council meeting, remember that science and ethics are on your side.

Alley Cat Allies is helping communities shake institutional cruelty and go humane. Never lose sight of the power of your voice in the movement for lifesaving change. A city council member will be far more open to a constituent who approaches them with TNR success studies in hand to advocate for humane policies.

With that in mind, I encourage you to be bold for the cats who need us. If you think your community can do better, speak out to make it happen. And know that in the debate of TNR versus killing, compassion holds all the cards.

Read the full study from Animals here.

Visit our TNR Research Compendium at alleycat.org/Research.